Vitamin K comes in two forms, and it is important to understand the differences between them before devising your nutritional plan of attack.

Two Basic Types of Vitamin K

Vitamin K can be classified as either K1 or K2:

Vitamin K1: Found in green vegetables, K1 goes directly to your liver and helps you maintain a healthy blood clotting system. (This is the kind of K that infants need to help prevent a serious bleeding disorder.)

It is also vitamin K1 that keeps your own blood vessels from calcifying, and also helps your bones retain calcium and develop the right crystalline structure.

Vitamin K2: Bacteria produce this type of vitamin K. It is present in high quantities in your gut, but unfortunately is not absorbed from there and therefore most of it is passed out in your stool.

K2 goes straight to vessel walls, bones, and tissues other than the liver. It is present in fermented foods, particularly cheese and the Japanese foodnatto, which is by far the richest source of K2.

Making matters even more complex, there are several different forms of vitamin K2.

MK8 and MK9 come primarily from dairy products. MK4 and MK7 are the two most significant forms of K2, and act very differently in your body:

MK4 is a synthetic product, very similar to vitamin K1, and your body is capable of converting K1 into MK4. However, MK4 has a very short half-life of about one hour, making it a poor candidate as a dietary supplement. After reaching your intestines, it remains mostly in your liver, where it is useful in synthesizing blood-clotting factors.

MK7 is a newer agent with more practical applications because it stays in your body longer; its half-life is three days, meaning you have a much better chance of building up a consistent blood level, compared to MK4 or K1. MK7 is extracted from the Japanese food called natto.

For those who are interested in getting a supply of vitamin K2 we do have it in our store.

Research results are similarly encouraging for the benefits of vitamin K to your cardiac health.

In 2004, the Rotterdam Study, which was the first study demonstrating the beneficial effect of vitamin K2, showed that those who consumed 45 mcg of K2 daily lived seven years longer than those getting 12 mcg per day.

In a subsequent study called the Prospect Study, 16,000 people were followed for 10 years. Researchers found that each additional 10 mcg of K2 in the diet resulted in 9 percent fewer cardiac events.

There is also research emerging that vitamin K can help protect against brain disease. However, it is too early to say exactly what types of damage it prevents, and how, but it is an area of intense interest to vitamin K scientists right now.

Getting More Vitamin K into Your Diet

For vitamin K2, cheese and especially cheese curd is an excellent source. The starter ferment for both regular cheese and curd cheese contains bacteria—lactococci and proprionic acids bacteria—which both produce K2. You get the benefits of these bacteria when you consume them.

Both types of cheese have the same amount of K2, but curd cheese has less fat. If you eat 100 grams of cheese daily, you get 45 mcg of vitamin K2, which will lower your risk for heart attack by 50 percent, according to existing studies.

You can obtain all the K2 you'll need (about 200 micrograms) by eating 15 grams of natto daily, which is half an ounce. It's a small amount and very inexpensive. It'll only shrink your wallet by about two dollars a month.

If you don't care for the taste of natto, the next best thing is a supplement. Remember you must always take your vitamin K supplement with fat since it is fat-soluble and won't be absorbed without it.

You need not worry about overdosing on K2—people have been given a thousand-fold increase over the recommended dose over the course of three years have shown no adverse reactions (i.e., no increased clotting tendencies).

Although the exact dosing is yet to be determined, Dr. Vermeer recommends between 45 mcg and 185 mcg daily for adults. You must use caution on the higher doses if you take anticoagulants, but if you are generally healthy and not on these types of medications, I suggest 150 mcg daily.

It is quite likely that doses of several times that amount are safe for the average person, but we just lack the research to confirm it at this time.

Vitamin D is Vitamin K's Best Friend

Dr. Vermeer makes the point that vitamin K will never be able to do its work alone. It needs collaborators—and vitamin D is an important one.

There is a synergistic effect between vitamins D and K.

These two agents work together to increase MGP, or Matrix GLA Protein, which is the protein responsible for protecting your blood vessels from calcification. In fact, MGP is so important that it can be used as a laboratory measure of your vascular and cardiac status.

If you are concerned about your bones, you must balance a nutritional triad:

vitamin D

vitamin K

calcium

Increasing calcium is good for your bones but not so good for your arteries, which can become calcified. Vitamin K protects your blood vessels from calcifying when in the presence of high calcium levels. So you really must pay attention to the synergism of all three of these nutrients if you want to optimize your benefits.

Laboratory Testing for Vitamin K is in its Infancy

Vitamin K measurements in blood plasma can be done accurately, but the results are really not helpful because they mainly reflect "what you ate yesterday," according to Dr. Vermeer.

Because there are no good laboratory assessments, he and his team have developed and patented a very promising laboratory test to assess vitamin K levels indirectly by measuring circulating MGP. Their studies have indicated this to be a very reliable method to assess the risk for arterial calcification—hence cardiac risk.

They are hoping to have this test available to the public within one to two years for a reasonable price, and several labs are already interested.

Additionally, they are working on developing a home test that would be available at your neighborhood drug store.

At this time, however, there is really no commercial test that would give you meaningful information. But since nearly 100 percent of people don't get sufficient amounts of vitamin K from their diet to reap its health benefits, you can assume you need to bump up your vitamin K levels by modifying your diet or taking a high quality supplement.

Disclaimer: The entire contents of this website are based upon the opinions of Dr. Mercola, unless otherwise noted. Individual articles are based upon the opinions of the respective author, who retains copyright as marked. The information on this website is not intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice. It is intended as a sharing of knowledge and information from the research and experience of Dr. Mercola and his community. Dr. Mercola encourages you to make your own health care decisions based upon your research and in partnership with a qualified health care professional. If you are pregnant, nursing, taking medication, or have a medical condition, consult your health care professional before using products based on this content.

If you want to use an article on your site please click here. This content may be copied in full, with copyright, contact, creation and information intact, without specific permission, when used only in a not-for-profit format. If any other use is desired, permission in writing from Dr. Mercola is required.

Disclaimer: The entire contents of this website are based upon the opinions of Dr. Mercola, unless otherwise noted. Individual articles are based upon the opinions of the respective author, who retains copyright as marked. The information on this website is not intended to replace a one-on-one relationship with a qualified health care professional and is not intended as medical advice. It is intended as a sharing of knowledge and information from the research and experience of Dr. Mercola and his community. Dr. Mercola encourages you to make your own health care decisions based upon your research and in partnership with a qualified health care professional. If you are pregnant, nursing, taking medication, or have a medical condition, consult your health care professional before using products based on this content.

If you want to use an article on your site please click here. This content may be copied in full, with copyright, contact, creation and information intact, without specific permission, when used only in a not-for-profit format. If any other use is desired, permission in writing from Dr. Mercola is required.